Adsorption of Zn(2+) and Ni(2+) in a binary aqueous solution by biosorbents derived from sawdust and water hyacinth (Eichhornia crassipes).

The Zn(2+) and Ni(2+) adsorption capacities of six biosorbents derived from water hyacinth (Eichhornia crassipes) (WH) and sawdust (SD) were investigated, with activated carbon as the control. The biosorbents were raw biomass (WH, SD), charred WH (BWH) and SD and sulphonated bio-chars of WH and SD. The effect of the initial solution pH and Zn(2+) and Ni(2+) concentrations on adsorption capacity was studied, and adsorption isotherms for Zn(2+) and Ni(2+) evaluated.

Adsorption kinetics, isotherms and thermodynamics of atrazine removal using a banana peel based sorbent.

Atrazine removal from water by treated banana peels was studied. The effect of pH, contact time, initial atrazine concentration, and temperature were investigated. Batch experiments demonstrated that 15 g L(-1) adsorbent dosage removed 90-99% of atrazine from 1-150 ppm aqueous solutions.

Removal of 2,4-dichlorophenoxyacetic acid by calcined Zn-Al-Zr layered double hydroxide.

The adsorption equilibrium, kinetics, and thermodynamics of removal of 2,4-dichlorophenoxy-acetic acid (2,4-D) from aqueous solutions by a calcined Zn-Al layered double hydroxide incorporated with Zr(4+) were studied with respect to time, temperature, pH, and initial 2,4-D concentration. Zr(4+) incorporation into the LDH was used to enhance 2,4-D uptake by creating higher positive charges and surface/layer modification of the adsorbent. The LDH was capable of removing up to 98% of 2,4-D from 5 to 400 ppm aqueous at adsorbent dosages of 500 and 5000 mg L(-1).

Towards p-type conductivity in SnO2 nanocrystals through Li doping.

This paper examines electrical transport properties and Li doping in SnO(2) synthesized by the sol-gel method. Solid-state (7)Li-NMR lineshapes reveal that Li ions occupy two distinct sites with differing dynamic mobilities. The chemical exchange rate between the two sites is, however, too slow for detection on the NMR timescale.

Room temperature Cl(2) sensing using thick nanoporous films of Sb-doped SnO(2).

Thick film resistive Cl(2) sensors were fabricated using SnO(2) doped with Sb. The nanocrystalline powders of Sb-doped SnO(2) synthesized by a sol-gel method were compressed into an 800 µm thick pellet. The fabricated sensors were tested against gases like Cl(2), Br(2), HCl, NO, NO(2), CHCl(3), NH(3) and H(2).